A hotel operator has been fined after dozens of guests and staff fell ill due to being exposed to Legionella bacteria in a hot tub.

BDL Select Operations Ltd, which operated the then-Landmark Hotel, now the Hilton Doubletree in Dundee, was fined £54,000 over the outbreak.

In total, 65 people fell ill, with 18 confirmed to have contracted Pontiac Fever, a non-fatal, flu-like illness caused by the same type of Legionella bug that causes Legionnaires' disease.

Dundee Sheriff Court heard how safety checks on the spa pool at the hotel's leisure club were not being correctly carried out following the sacking of the club's manager in January 2011.

As a result of that departure, the hot tub was not fully drained, cleaned or disinfected for more than two months before the outbreak.

Furthermore, a "backwashing" job on its filters, which industry bodies recommend is carried out daily, was only done five times between February 6 and March 17, 2011.

A chlorine injector on the pool failed in March 2011, causing chlorine levels in the pool to fall to dangerous levels and allowing bacteria to breed in it.

It was eventually put out of action but left switched on to prevent water stagnating. That kept the water in the temperature zone, which allows the Legionella bug to proliferate, and also agitated the water, allowing infected water droplets to become airborne.

Fiscal depute Emma Stewart told the court that after the outbreak was identified, Legionella bacteria was found in water samples taken from poolside showers and in showers in the men's changing rooms.

She said: "As a result, staff members and guests were exposed to Legionella bacteria. In total, one staff member and 17 guests were confirmed to have contracted Pontiac Fever.

"When the hot tub was closed it was left on and, over that weekend, four regular members of the club were allowed to use it for around 20 minutes. All four later fell ill and three were confirmed to have Pontiac Fever.

"An investigation was undertaken and the spa pool was later decommissioned entirely. Some staff were trained how to test water but had little knowledge on how to interpret the results. No information was made available to staff in that regard."

BDL Select Operations Ltd pleaded guilty on indictment to two charges under the Health and Safety At Work Act 1974.

Defence advocate Barry Smith said: "The company acquired the hotel in 2008 and spent £2.75m on it, including £140,000 on the leisure club. Considerably more money has been spent since this incident, some £1m."

Handing down the £54,000 fine, Sheriff George Way said: "Clearly this is a matter of significant public concern.

"There have been fatalities caused by airborne risks and failures to prevent those risks.

"It is only good fortune that the actual consequences of the failures are not more serious."

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